Some of these are grammar mistakes (or clarifications). Some are arguable misuse of words (though word use is always changing). Some are personal preferences and affections.
So here are three meta-rules about grammar and grammar mistakes:
1. The purpose of grammar (and spelling, etc.) is to communicate clearly. If the communication is clear, it's okay if a rule has been broken.
2. Regardless of #1, some people will judge you and your writing based on your adherence to the rules. In a sense, your use of the rules is communicating about you, not just about your topic. It's like you'll be judged on what you wear, fairly or not.
3. As always, and in keeping with #1-2, it's better to know and understand the rules before you break them (as it lets you evaluate whether a rule should be broken).
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20 Common Grammar Mistakes That (Almost) Everyone Makes
A list of some of the most common grammatical errors that routinely make it into print.
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Thanks for the link! I think the author was letting out some steam there towards the end! That is, the list starts innocently enough, but by the end, the author is reduced in places to say "Stop. Just stop!"
Indeed, +Chris Pitchford. Though, ultimately, that's what all grammar and spelling rules are, for good causes are bad. They certainly don't exist as Platonic Ideals or some God-mandated set of stone tablets or Physical Laws.
And I say that as someone who corrects a lot of people's grammar. 😉